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-rw-r--r--gold/ChangeLog13
-rw-r--r--gold/common.cc101
-rw-r--r--gold/options.h4
-rw-r--r--gold/symtab.h12
4 files changed, 104 insertions, 26 deletions
diff --git a/gold/ChangeLog b/gold/ChangeLog
index f32f46f..b4c0f6f 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,5 +1,18 @@
2009-12-30 Ian Lance Taylor <iant@google.com>
+ PR 10931
+ * options.h (class General_options): Add --sort-common option.
+ * symtab.h (class Symbol_table): Define Sort_commons_order enum.
+ * common.cc (Sort_common): Add sort_order parameter to
+ constructor. Add sort_order_ field.
+ (Sort_commons::operator): Check sort_order_.
+ (Symbol_table::allocate_commons): Determine the sort order.
+ (Symbol_table::do_allocate_commons): Add sort_order parameter.
+ Change all callers.
+ (Symbol_table::do_allocate_commons_list): Likewise.
+
+2009-12-30 Ian Lance Taylor <iant@google.com>
+
PR 10916
* symtab.cc (Symbol_table::add_from_relobj): When not exporting
symbols from this object, don't change the visibility of an
diff --git a/gold/common.cc b/gold/common.cc
index c5d830e..c4ff047 100644
--- a/gold/common.cc
+++ b/gold/common.cc
@@ -64,21 +64,26 @@ Allocate_commons_task::run(Workqueue*)
this->symtab_->allocate_commons(this->layout_, this->mapfile_);
}
-// This class is used to sort the common symbol by size. We put the
-// larger common symbols first.
+// This class is used to sort the common symbol. We normally put the
+// larger common symbols first. This can be changed by using
+// --sort-commons, which tells the linker to sort by alignment.
template<int size>
class Sort_commons
{
public:
- Sort_commons(const Symbol_table* symtab)
- : symtab_(symtab)
+ Sort_commons(const Symbol_table* symtab,
+ Symbol_table::Sort_commons_order sort_order)
+ : symtab_(symtab), sort_order_(sort_order)
{ }
bool operator()(const Symbol* a, const Symbol* b) const;
private:
+ // The symbol table.
const Symbol_table* symtab_;
+ // How to sort.
+ Symbol_table::Sort_commons_order sort_order_;
};
template<int size>
@@ -94,22 +99,48 @@ Sort_commons<size>::operator()(const Symbol* pa, const Symbol* pb) const
const Sized_symbol<size>* psa = symtab->get_sized_symbol<size>(pa);
const Sized_symbol<size>* psb = symtab->get_sized_symbol<size>(pb);
- // Sort by largest size first.
+ // The size.
typename Sized_symbol<size>::Size_type sa = psa->symsize();
typename Sized_symbol<size>::Size_type sb = psb->symsize();
+
+ // The alignment.
+ typename Sized_symbol<size>::Value_type aa = psa->value();
+ typename Sized_symbol<size>::Value_type ab = psb->value();
+
+ if (this->sort_order_ == Symbol_table::SORT_COMMONS_BY_ALIGNMENT_DESCENDING)
+ {
+ if (aa < ab)
+ return false;
+ else if (ab < aa)
+ return true;
+ }
+ else if (this->sort_order_
+ == Symbol_table::SORT_COMMONS_BY_ALIGNMENT_ASCENDING)
+ {
+ if (aa < ab)
+ return true;
+ else if (ab < aa)
+ return false;
+ }
+ else
+ gold_assert(this->sort_order_
+ == Symbol_table::SORT_COMMONS_BY_SIZE_DESCENDING);
+
+ // Sort by descending size.
if (sa < sb)
return false;
else if (sb < sa)
return true;
- // When the symbols are the same size, we sort them by alignment,
- // largest alignment first.
- typename Sized_symbol<size>::Value_type va = psa->value();
- typename Sized_symbol<size>::Value_type vb = psb->value();
- if (va < vb)
- return false;
- else if (vb < va)
- return true;
+ if (this->sort_order_ == Symbol_table::SORT_COMMONS_BY_SIZE_DESCENDING)
+ {
+ // When the symbols are the same size, we sort them by
+ // alignment, largest alignment first.
+ if (aa < ab)
+ return false;
+ else if (ab < aa)
+ return true;
+ }
// Otherwise we stabilize the sort by sorting by name.
return strcmp(psa->name(), psb->name()) < 0;
@@ -120,10 +151,27 @@ Sort_commons<size>::operator()(const Symbol* pa, const Symbol* pb) const
void
Symbol_table::allocate_commons(Layout* layout, Mapfile* mapfile)
{
+ Sort_commons_order sort_order;
+ if (!parameters->options().user_set_sort_common())
+ sort_order = SORT_COMMONS_BY_SIZE_DESCENDING;
+ else
+ {
+ const char* order = parameters->options().sort_common();
+ if (*order == '\0' || strcmp(order, "descending") == 0)
+ sort_order = SORT_COMMONS_BY_ALIGNMENT_DESCENDING;
+ else if (strcmp(order, "ascending") == 0)
+ sort_order = SORT_COMMONS_BY_ALIGNMENT_ASCENDING;
+ else
+ {
+ gold_error("invalid --sort-common argument: %s", order);
+ sort_order = SORT_COMMONS_BY_SIZE_DESCENDING;
+ }
+ }
+
if (parameters->target().get_size() == 32)
{
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
- this->do_allocate_commons<32>(layout, mapfile);
+ this->do_allocate_commons<32>(layout, mapfile, sort_order);
#else
gold_unreachable();
#endif
@@ -131,7 +179,7 @@ Symbol_table::allocate_commons(Layout* layout, Mapfile* mapfile)
else if (parameters->target().get_size() == 64)
{
#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
- this->do_allocate_commons<64>(layout, mapfile);
+ this->do_allocate_commons<64>(layout, mapfile, sort_order);
#else
gold_unreachable();
#endif
@@ -144,20 +192,25 @@ Symbol_table::allocate_commons(Layout* layout, Mapfile* mapfile)
template<int size>
void
-Symbol_table::do_allocate_commons(Layout* layout, Mapfile* mapfile)
+Symbol_table::do_allocate_commons(Layout* layout, Mapfile* mapfile,
+ Sort_commons_order sort_order)
{
if (!this->commons_.empty())
this->do_allocate_commons_list<size>(layout, COMMONS_NORMAL,
- &this->commons_, mapfile);
+ &this->commons_, mapfile,
+ sort_order);
if (!this->tls_commons_.empty())
this->do_allocate_commons_list<size>(layout, COMMONS_TLS,
- &this->tls_commons_, mapfile);
+ &this->tls_commons_, mapfile,
+ sort_order);
if (!this->small_commons_.empty())
this->do_allocate_commons_list<size>(layout, COMMONS_SMALL,
- &this->small_commons_, mapfile);
+ &this->small_commons_, mapfile,
+ sort_order);
if (!this->large_commons_.empty())
this->do_allocate_commons_list<size>(layout, COMMONS_LARGE,
- &this->large_commons_, mapfile);
+ &this->large_commons_, mapfile,
+ sort_order);
}
// Allocate the common symbols in a list. IS_TLS indicates whether
@@ -169,7 +222,8 @@ Symbol_table::do_allocate_commons_list(
Layout* layout,
Commons_section_type commons_section_type,
Commons_type* commons,
- Mapfile* mapfile)
+ Mapfile* mapfile,
+ Sort_commons_order sort_order)
{
typedef typename Sized_symbol<size>::Value_type Value_type;
typedef typename Sized_symbol<size>::Size_type Size_type;
@@ -202,10 +256,9 @@ Symbol_table::do_allocate_commons_list(
if (!any)
return;
- // Sort the common symbols by size, so that they pack better into
- // memory.
+ // Sort the common symbols.
std::sort(commons->begin(), commons->end(),
- Sort_commons<size>(this));
+ Sort_commons<size>(this, sort_order));
// Place them in a newly allocated BSS section.
elfcpp::Elf_Xword flags = elfcpp::SHF_WRITE | elfcpp::SHF_ALLOC;
diff --git a/gold/options.h b/gold/options.h
index d8f5fb9..872d142 100644
--- a/gold/options.h
+++ b/gold/options.h
@@ -819,6 +819,10 @@ class General_options
N_("Add DIR to link time shared library search path"),
N_("DIR"));
+ DEFINE_optional_string(sort_common, options::TWO_DASHES, '\0', NULL,
+ N_("Sort common symbols by alignment"),
+ N_("[={ascending,descending}]"));
+
DEFINE_bool(strip_all, options::TWO_DASHES, 's', false,
N_("Strip all symbols"), NULL);
DEFINE_bool(strip_debug, options::TWO_DASHES, 'S', false,
diff --git a/gold/symtab.h b/gold/symtab.h
index cac7bee..8ee2091 100644
--- a/gold/symtab.h
+++ b/gold/symtab.h
@@ -1195,6 +1195,14 @@ class Symbol_table
PREDEFINED,
};
+ // The order in which we sort common symbols.
+ enum Sort_commons_order
+ {
+ SORT_COMMONS_BY_SIZE_DESCENDING,
+ SORT_COMMONS_BY_ALIGNMENT_DESCENDING,
+ SORT_COMMONS_BY_ALIGNMENT_ASCENDING
+ };
+
// COUNT is an estimate of how many symbosl will be inserted in the
// symbol table. It's ok to put 0 if you don't know; a correct
// guess will just save some CPU by reducing hashtable resizes.
@@ -1603,13 +1611,13 @@ class Symbol_table
// Allocate the common symbols, sized version.
template<int size>
void
- do_allocate_commons(Layout*, Mapfile*);
+ do_allocate_commons(Layout*, Mapfile*, Sort_commons_order);
// Allocate the common symbols from one list.
template<int size>
void
do_allocate_commons_list(Layout*, Commons_section_type, Commons_type*,
- Mapfile*);
+ Mapfile*, Sort_commons_order);
// Implement detect_odr_violations.
template<int size, bool big_endian>
generated by cgit v1.1 at 2024-11-24 01:07:42 +0000